Syringe adapter



p 1968 J. HIGGINS ET AL 3,402,714

SYR INGE ADAPTER Filed Feb. 5. 1967 IIIIII .u n ino/ I Int/672E765 72ml. H

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United States PatentO 1 3,402,714. l SYRINGE ADAPTER John L. Higgins, Daytona Beach, Fla., and Peter A. Stevens St. Louis, Mo., assignors to Brunswick v Corporation, a corporation of Delaware i Filed Feb. 3; 1967,'Ser. No. 613,781

- Claims.'(Cl. 128-221) This invention relates to hypodermic needles and in particular to means for adapting a slip type syringe tip to one accommodating a Luer lock type needle hub.

In one conventional form of hypodermic syringe formed with a plastic barrel, the forward end of the barrel defines a frusto-conicaloutwardly-narrowing tip adapted for a slip connection of a corresponding needle hub coaxially' thereto. In certain applications, it is desirable to provide a threaded connection of the needle hub to the barrel tip. Heretofore, such plastic barrel tips have been provided with threads for-connection of the Luer lock type needle hub. However, it has been found that such threads tend to strip, and such thread structures have not proven completely satisfactory. A numberof different forms of metal adapters have heretofore been provided for attachment to, glass barrel tips and the like, but no fully satisfactory adapter. has been. available for converting such plastictipped barrels for usewith metal Luer lock type needle -hubs,.The pre sent invention comprehends an improved adapter structure for effecting such adaptation.

Thus, a principal feature of the present invention is the provision of a new and improved adapter for use with a plastic frustoconical outwardly narrowing barrel tip arranged for slip connection of a corresponding needle hub coaxially theretoto. a structure adapted for connection of a Luer lock type needle hub to the syringe.

A further feature of the invention is the provision of such a syringe adapter comprising an annular adapter having an axially outer tubular portion defining a thread for threaded engagement of a Luer lock type needle hub therewith, and an axially inner, radially inturned gripping means biting into said barrel tip for retaining the adapter effectively positively on said tip against axially outward displacement.

Another feature of the invention is the provision of such a syringe adapter wherein the gripping means comprises an annular flange defining a plurality of teeth biting into the barrel tip.

A further feature of the invention is the provision of such a syringe adapter wherein the flange is substantially frusto-conical narrowing axially outwardly.

Still another feature of the invention is the provision of such -a syringe adapter wherein the gripping means effectively centers the adapting means coaxially of the tip.

Yet another feature of the invention is the provision of such a syringe adapter wherein the gripping means comprises an overcenter means providing increased resistance to outward axial displacement as an incident to an initial urging of the adapting means axially outwardly.

Another feature of the invention is the provision of such a syringe adapter wherein the gripping means com- 3,402,714 Patented Sept. 24, 1968 prises a plurality of teeth substantially fully embedded in the barrel tip.

Still another feature of the invention is the provision of such a syringe adapter wherein the adapting means is radially spaced from the barrel tip other than at the inturned gripping means.

A further feature of the invention is the provision of such a syringe adapter wherein the adapting means has an axial length less than that of the barrel tip.

A still further feature of the invention is the provision of such a syringe adapter wherein the gripping means comprises means for providing increased resistance to outward axial displacement as an incident to an initial urging of the adapting means axially outwardly.

Yet another feature of the invention is the provision of such a syringe adapter wherein the adapting means comprises a thin walled tubular element and the gripping means comprises a serrated inturned end of the element having teeth projecting approximately the thickness of the element into the barrel tip.

Other features and advantages of the invention will be apparent from the following description taken in connection with the accompanying drawing wherein:

FIGURE 1 is a side elevation of a syringe having an adapting means embodying the invention;

FIGURE 2 is a fragmentary enlarged exploded view of the barrel tip and adapting means;

FIGURE 3 is a fragmentary enlarged diametric section of the adapting means as initially installed on the barrel end;

FIGURE 4 is a transverse section taken substantially along the line 4-4 of FIGURE 3;

FIGURE 5 is a fragmentary diametric section similar to that of FIGURE 3, but with a setting tool inserted into the adapting means to initiate a locking of the adapting means to the barrel tip;

FIGURE 6 is a diametric section similar tothat of FIGURE 5, but with the setting tool as disposed upon completion of the securing operation; and

FIGURE 7 is a transverse section taken substantially along the line 77 of FIGURE 6.

In the exemplary embodiment of the invention as disclosed in the drawing, a hypodermic syringe generally designated 10 includes a tubular barrel 11 receiving a plunger 12 for axial reciprocal movement therein, and carrying at a front end a needle 13. The plunger 12 is provided with an inner piston portion 14 sealingly, slidingly engaging the barrel 11 for moving fluid through a generally tubular tip 15 on the front end of the barrel 11. Needle 13 is connected to the tip 15 by a new and improved adapter 16 permitting the needle 13 to be elfectively locked to the barrel in use.

More specifically, needle 13 is provided with a Luer lock type hub 17 adapted to have threaded engagement with an internal thread 18 of the adapter 16. Adapter 16 is preferably formed of thin sheet metal and may have the thread 18 formed therein as by spinning. As seen in FIG- URE 3, the adapter includes an outer tubular portion 19 in which the thread 18 is formed, and an inner, radially inturned flange 20 which as seen in FIGURE 4 is provided with a serrated inner edge 21. The flange 20 is frustoconical narrowing outwardly and the teeth 22 of the serrated edge 21 bear against the outwardly narrowing frusto-conical outer surface 23 of the barrel tip 15 when the adapter is moved downwardly onto the tip.

The adapter 16 is effectively positively secured to the tip 15 which is formed of a bitable material such as plastic, by forcing the teeth 22 of flange edge 21 into the plastic tip by a suitable tool T, as shown in FIGURE 5. More specifically, the tool T may include an annular presser portion 24 adapted to engage the teeth 22 and urge them 3 coaxially'radially inwardly into the plastic tip material until the teeth 22 are substantially embedded in the tip as shown in FIGURE 6. The tool T is then withdrawn axially from the assembled adapted and tip structure leaving, the adapter substantially positively fixed to the tip against axial displacement outwardly tlierefromi In the installed'arrangement of the adapter as illustrated in FIGURES 6 and 7 of the drawing, ,the frusto-conical flange 20 effectively defines an overcenter device which provides increased resistance to outward axial displacement of the adapter 16 as an incident to an initial urging of the adapter axially outwardly relative to the tip 15. More specifically, such an axial outward urging causes the flange 20 to tend toward a more nearly perpendicular relationship to the axis of the tip 15 which is resisted by the tip material against further penetration of the serrated edge 21 thereinto and by the effectively nonradially expandable structure of the flange 20. In the installed position of FIGURE 6, the teeth 22 are effectively fully embedded into the tip and thus provide effectively maximum resistance to deflection thereof by such axial outward forces. As shown in FIGURE 6, the radial extent of the teeth 22 is generally similar to the thickness of the flange 20.

As further shown in FIGURE 6, the length of the tubular portion 19 of the adapter 16 is preferably slightly less than the length of the barrel tip 15 whereby the needle hub 17 may be sealingly engaged with the surface 23 of the tip 15 while threadedly engaging the adapter thread 18.

Thus, adapter 16 provides in a plastic barrel type syringe a metal connecting means for connection of a Luer lock type needle hub to the barrel avoiding the thread stripping often occurring in the conventional plastic thread syringes. The syringe may be a conventional slip lock type syringe, as the adapter may be readily installed at anytime by the user when it is desired to utilize the syringe with a Luer lock type needle. Thus, the tip 15 need not be provided with grooves or the like for cooperation with retaining means on conventional adapters, but may comprise a standard slip lock tip structure thereby effectively maximizing efficiency and minimizing cost to the user. Because of the overcenter type ngagement of the serrated flange with the barrel tip, the attachment of the adapter to the tip may be made with relatively light force, while yet the adapter is effectively positively secured to the tip.

While we have shown and described one embodiment of our invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made without departing from the spirit and scope of the invention as defined in the appended claims. a r

We claim:

1. In a syringe having a barrel provided with a plastic, frusto-conical outwardly narrowing tip for slip connection of a correspondingueedle hub coaxially thereto, m ans for adapting saidtlfa'for -locked conriection of a Luer lock type needle hubth'ereto comprisingz i an annular adapter having an axially outer itubular portion .de'finirig 'a t hread ffor thre adedenga'gement of a Luer loci; type needle hub. therewith, and an axially inner, radially inturned gripping means biting into said barrel tip for-retaining the adapter effectively positively on said tip against. axially outward displacement. r

2. The syringe means of claim 1' wherein said gripping means comprises an annular flange defining a plurality'of teeth biting into said barrel tip. i 1

3. The syringe means of claim 2 wherein said flange is substantially frusto-conical narrowing axially outwardly.

4. The syringe meansof claim l wherein said gripping means effectively centers the adapting means coaxially of said tip.

5. The syringe means of claim 1 wherein said gripping means comprises an overcenter means providing increased resistance to outward axial displacement as an incident to an initial urging of the adapting means axially outwardly.

6. The syringe means of claim 1 wherein said gripping means comprises a plurality of teeth substantially fully embedded in said barrel tip. v

7. The syringe means of claim 1 wherein said adapting means is radially spaced from said barr l tip other than at said inturned gripping means.

8. The syringe means of claim 1 wherein said adapting means has an axial length less than that of said barrel tip.

9. The syringe means of claim 1 wherein said gripping means comprises means forproviding increasedresistance to outward axial displacement as an incident to an initial urging of the adapting means axially outwardly.

10. The syringe means of claim 1 wherein said adapting means comprises a thin walled tubular element and said gripping means comprises a serrated inturned end of said element having teeth projecting approximately the 'thickness of said element into said barrel tip.

No references cited. 

